:root{
  color-scheme:light;
  --bg:#FAFAFD;--bg-deep:#F0F0F8;--panel:#FFFFFF;--panel-2:#F2F2F8;
  --border:#E4E3EF;--border-soft:#ECEBF4;
  --accent:#6A5BF7;--accent-2:#3D8BFF;--accent-dark:#4636D1;
  --text:#15132B;--muted:#5E5C76;--faint:#8C8AA5;--logo-grey:#8A88A2;
  --success:#14B8A6;--success-ink:#0E7D71;--success-tint:#E1F6F3;--success-ring:rgba(20,184,166,.2);
  --warn:#D9930D;--error:#E0435A;--ink-frame:#1E1B3A;--on-ink:#FFFFFF;--on-ink-muted:#B6B3D2;
  --lilac:#ECEAFE;--lilac-deep:#DFD9FF;--sky:#EBF2FF;--sky-deep:#D8E6FF;--mist:#F5F2FA;--mist-deep:#E5DFF2;
  --chip-glass:rgba(255,255,255,.8);
  --dot-1:#EF97A4;--dot-2:#F1C672;--dot-3:#C9C4E6;
  --grid-line:rgba(21,19,43,.04);--glow-lilac:rgba(156,138,255,.34);--glow-sky:rgba(104,168,255,.26);--bar-bg:rgba(250,250,253,.88);
  --veil:rgba(21,19,43,.3);
  --flag-white:#FFFFFF;--flag-us-red:#C3283D;--flag-us-blue:#2F3A7A;--flag-hk:#DE2910;--flag-sg:#E3303F;--flag-jp:#C8102E;--flag-ch:#DA291C;--flag-ca:#D52B1E;--flag-ring:rgba(21,19,43,.14);
  --clear:transparent;
  --grad:linear-gradient(100deg,var(--accent) 0%,var(--accent-2) 100%);
  --grad-soft:linear-gradient(120deg,var(--lilac) 0%,var(--sky-deep) 100%);
  --shadow-win:0 1px 2px rgba(21,19,43,.05),0 14px 30px -14px rgba(70,54,209,.16),0 44px 96px -18px rgba(106,91,247,.12);
  --shadow-card:0 1px 2px rgba(21,19,43,.06),0 18px 40px -12px rgba(106,91,247,.2);
  --shadow-pill:0 10px 24px -10px rgba(21,19,43,.35);
  --shadow-cta:0 14px 28px -12px rgba(70,54,209,.55),inset 0 1px 0 rgba(255,255,255,.22);
  --shadow-soft:0 1px 2px rgba(21,19,43,.05),0 6px 16px -8px rgba(106,91,247,.18);
  --shadow-frame:0 18px 36px -18px rgba(30,27,58,.5);
  --shadow-badge:0 2px 6px rgba(21,19,43,.14);
  --hi-edge:inset 0 1px 0 rgba(255,255,255,.95);--hi-cell:inset 0 1px 0 rgba(255,255,255,.75);
  --r-xl:22px;--r-lg:16px;--r-md:12px;--r-sm:8px;--r-xs:6px;--r-button:14px;--r-avatar:10px;--r-frame:18px;--r-pill:999px;--r-round:50%;
  --font-display:"Inter","Noto Sans SC","PingFang SC","Hiragino Sans","Yu Gothic","Apple SD Gothic Neo","Malgun Gothic","Microsoft YaHei",system-ui,sans-serif;
  --font-body:"Inter","Noto Sans SC","PingFang SC","Hiragino Sans","Yu Gothic","Apple SD Gothic Neo","Malgun Gothic","Microsoft YaHei",system-ui,-apple-system,sans-serif;
  --font-mono:"JetBrains Mono",ui-monospace,"SFMono-Regular",Menlo,Consolas,monospace;
  --body-size:16px;--body-leading:1.5;--weight-body:400;--weight-medium:500;--weight-semibold:600;--weight-bold:700;--weight-display:800;
  --display-size:64px;--heading-size:38px;--subheading-size:24px;--small-size:14px;
  --gutter:60px;--shell-max:1440px;--header-height:72px;--anchor-gap:88px;--toc-offset:16px;--section-anchor:100px;
  --space-section:72px;--space-card:24px;
  --ease:cubic-bezier(.2,.7,.2,1);--fast:.2s;--reveal-time:.35s;
}
*,*::before,*::after{box-sizing:border-box}
html{-webkit-text-size-adjust:100%;scroll-behavior:smooth;scroll-padding-top:var(--anchor-gap)}
body{margin:0;background:var(--bg);color:var(--text);font-family:var(--font-body);font-size:var(--body-size);line-height:var(--body-leading);font-weight:var(--weight-body);-webkit-font-smoothing:antialiased;text-rendering:optimizeLegibility}
a{color:inherit;text-decoration:none}
button,input,select,textarea{font:inherit;color:inherit}
button{cursor:pointer}
button:disabled{cursor:not-allowed}
img{max-width:100%;height:auto}
svg{flex-shrink:0;vertical-align:middle}
ul{margin:0;padding:0;list-style:none}
p{margin:0 0 1.25em}
h1,h2,h3,h4{font-family:var(--font-display);color:var(--text);overflow-wrap:break-word}
h1{font-size:var(--display-size);line-height:1.1;letter-spacing:-.02em;font-weight:var(--weight-display)}
h2{font-size:var(--heading-size);line-height:1.2;letter-spacing:-.02em;font-weight:var(--weight-display)}
h3{font-size:var(--subheading-size);line-height:1.35}
:focus-visible{outline:2px solid var(--accent);outline-offset:3px;border-radius:var(--r-xs)}
[hidden]{display:none!important}
.shell,.wrap{width:100%;max-width:var(--shell-max);padding-inline:var(--gutter);margin-inline:auto}
.shell>* , .wrap>* , .grid>*{min-width:0}
.section{padding-top:var(--space-section);padding-bottom:var(--space-section)}
.panel,.card{min-width:0;padding:var(--space-card);border:1px solid var(--border-soft);border-radius:var(--r-xl);background:var(--panel);box-shadow:var(--shadow-soft),var(--hi-edge)}
.panel-inset{background:var(--panel-2);border-radius:var(--r-lg);padding:var(--space-card)}
.grid{display:grid;gap:24px}
.grid-three{grid-template-columns:repeat(3,minmax(0,1fr))}
.grid-five{grid-template-columns:repeat(5,minmax(0,1fr))}
.no-break{white-space:nowrap}
.mono{font-family:var(--font-mono);font-variant-numeric:tabular-nums}
.muted{color:var(--muted)}
.small{font-size:var(--small-size)}
.sprite{position:absolute;width:0;height:0;overflow:hidden}
.sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip-path:inset(50%);white-space:nowrap;border:0}
.grad{background:var(--grad);-webkit-background-clip:text;background-clip:text;color:var(--clear);-webkit-text-fill-color:var(--clear)}
.cta-row{display:flex;flex-wrap:wrap;gap:12px;margin-top:32px}
.btn{display:inline-flex;align-items:center;justify-content:center;gap:10px;min-height:54px;padding:12px 26px;border:1px solid var(--clear);border-radius:var(--r-button);font-size:var(--body-size);font-weight:var(--weight-semibold);letter-spacing:-.005em;line-height:1.4;white-space:nowrap;flex-shrink:0;transition:transform var(--fast),box-shadow var(--fast),border-color var(--fast)}
.btn svg{width:18px;height:18px}
.btn-primary{background:var(--grad);color:var(--on-ink);box-shadow:var(--shadow-cta)}
.btn-primary:hover,.btn-primary.is-hover{transform:translateY(-1px)}
.btn-primary:active,.btn-primary.is-active{transform:translateY(1px);box-shadow:var(--shadow-soft)}
.btn-ghost,.btn-secondary{background:var(--panel);color:var(--text);border-color:var(--border);box-shadow:var(--shadow-soft)}
.btn-ghost:hover,.btn-secondary:hover{border-color:var(--lilac-deep)}
.btn:disabled,.btn[aria-disabled="true"]{background:var(--panel-2);color:var(--muted);box-shadow:none;border-color:var(--border)}
.btn-small{min-height:44px;padding:10px 16px;font-size:var(--small-size)}
.text-link{color:var(--accent-dark);text-decoration:underline;text-underline-offset:4px}
.reveal{transition:opacity var(--reveal-time) var(--ease),transform var(--reveal-time) var(--ease)}
.reveal.pending{opacity:0;transform:translateY(16px)}
.reveal.shown{opacity:1;transform:none}
.prose{max-width:78ch;line-height:1.85;overflow-wrap:break-word}
.prose h2{margin-top:2em;margin-bottom:.75em}
.prose h3{margin-top:1.6em}
.prose ul,.prose ol{padding-left:1.5em;margin-bottom:1.25em}
.prose ul{list-style:disc}
.prose a{color:var(--accent-dark);text-decoration:underline;text-underline-offset:3px}
code{font-family:var(--font-mono);overflow-wrap:anywhere;word-break:break-word;background:var(--panel-2);border-radius:var(--r-xs);padding:.1em .3em}
pre{max-width:100%;overflow-x:auto;padding:20px;border-radius:var(--r-md);background:var(--panel-2)}
pre code{white-space:pre;word-break:normal;overflow-wrap:normal;padding:0}
.decor-region{position:relative;overflow-x:clip}
#server-status{position:relative;display:block;min-width:0;width:100%;max-width:100%;overflow:hidden;margin-top:24px;margin-bottom:24px}
#server-status+*{margin-top:24px}
#server-status>*{min-width:0;max-width:100%}
/* Shared header */
#site-header{position:relative;z-index:60;min-height:var(--header-height)}
.topbar{position:relative;z-index:60;background:var(--bar-bg);border-bottom:1px solid var(--border-soft)}
.topbar-row{display:flex;align-items:center;flex-wrap:nowrap;min-height:var(--header-height);gap:36px}
.brand{display:inline-flex;align-items:center;gap:10px;font-family:var(--font-display);font-weight:var(--weight-display);font-size:19px;letter-spacing:-.015em;color:var(--text);flex-shrink:0;white-space:nowrap}
.brand img{width:32px;height:32px}
.brand-zh{font-weight:var(--weight-medium);color:var(--muted)}
.desktop-nav{display:flex;align-self:stretch;flex:1;min-width:0}
.tabs{display:flex;align-items:center;list-style:none;margin:0;padding:0;gap:2px;min-width:0;align-self:stretch}
.tabs li{display:flex;align-self:stretch}
.tabs a{position:relative;display:flex;align-items:center;padding:0 14px;font-size:14.5px;font-weight:var(--weight-medium);color:var(--muted);white-space:nowrap;transition:color var(--fast)}
.tabs a:hover{color:var(--text)}
.tabs a::after{content:"";position:absolute;left:14px;right:14px;bottom:-1px;height:2px;border-radius:var(--r-xs);background:var(--accent);opacity:0;transform:scaleX(.4);transition:opacity var(--fast),transform var(--fast)}
.tabs a:hover::after{opacity:.35;transform:scaleX(1)}
.tabs a[aria-current="page"]{color:var(--text);font-weight:var(--weight-semibold)}
.tabs a[aria-current="page"]::after{opacity:1;transform:none}
.bar-end{display:flex;align-items:center;gap:10px;flex-shrink:0;margin-left:auto}
.language{position:relative}
.lang{display:inline-flex;align-items:center;justify-content:center;gap:6px;min-width:44px;width:auto;height:38px;padding:0 12px;border:1px solid var(--border);border-radius:var(--r-pill);background:var(--panel);font:var(--weight-medium) 13.5px/1 var(--font-body);color:var(--muted);white-space:nowrap}
.lang span{white-space:nowrap}
.lang svg{width:15px;height:15px}
.lang-panel{position:absolute;right:0;top:calc(100% + 10px);z-index:90;min-width:180px;padding:6px;border:1px solid var(--border);border-radius:var(--r-md);background:var(--panel);box-shadow:var(--shadow-card)}
.lang-panel a{display:flex;align-items:center;min-height:44px;padding:10px 12px;border-radius:var(--r-sm);font-size:var(--small-size)}
.lang-panel a:hover,.lang-panel a[aria-current="true"]{background:var(--lilac);color:var(--accent-dark)}
.nav-login{display:inline-flex;align-items:center;justify-content:center;min-height:40px;padding:8px 20px;border-radius:var(--r-md);background:var(--text);color:var(--on-ink);font-size:var(--small-size);font-weight:var(--weight-semibold);box-shadow:var(--shadow-pill);white-space:nowrap}
.nav-login:hover{background:var(--ink-frame)}
.nav-toggle{display:none;align-items:center;justify-content:center;flex-direction:column;gap:4px;min-width:44px;min-height:44px;padding:10px;border:1px solid var(--border);border-radius:var(--r-md);background:var(--panel);color:var(--text)}
.nav-toggle-line{display:block;width:20px;height:2px;background:currentColor;border-radius:var(--r-xs)}
.nav-toggle[aria-expanded="true"] .nav-toggle-line:first-child{transform:translateY(6px) rotate(45deg)}
.nav-toggle[aria-expanded="true"] .nav-toggle-line:nth-child(2){opacity:0}
.nav-toggle[aria-expanded="true"] .nav-toggle-line:last-child{transform:translateY(-6px) rotate(-45deg)}
.nav-drawer{position:fixed;z-index:55;top:var(--header-height);right:0;left:0;height:calc(100dvh - var(--header-height));max-height:calc(100dvh - var(--header-height));overflow-y:auto;overscroll-behavior:contain;background:var(--panel);padding:20px var(--gutter) 32px;border-top:1px solid var(--border)}
.nav-drawer a{display:flex;align-items:center;width:100%;min-height:44px;padding:12px 16px;border-radius:var(--r-sm);color:var(--text)}
.nav-drawer a[aria-current]{background:var(--lilac);color:var(--accent-dark)}
.drawer-languages{margin-top:20px;padding-top:12px;border-top:1px solid var(--border)}
.nav-veil{position:fixed;z-index:50;inset:var(--header-height) 0 0;background:var(--veil);border:0}
html.nav-open{overflow:hidden}
/* Footer */
.site-footer{padding-top:56px;padding-bottom:28px;border-top:1px solid var(--border);background:var(--panel-2)}
.footer-grid{display:grid;grid-template-columns:1.25fr 1fr 1fr;gap:48px}
.footer-brand p{max-width:28em;margin-top:18px;color:var(--muted);font-size:var(--small-size);line-height:1.8}
.footer-title{font-size:var(--small-size);font-weight:var(--weight-bold);margin:0 0 14px}
.footer-links{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:6px 16px}
.footer-links a,.footer-languages a,.footer-legal a{display:inline-flex;align-items:center;min-height:28px;font-size:var(--small-size);color:var(--muted)}
.footer-links a:hover,.footer-languages a:hover,.footer-legal a:hover{color:var(--accent-dark)}
.footer-bottom{display:flex;align-items:center;justify-content:space-between;gap:20px;flex-wrap:wrap;border-top:1px solid var(--border);margin-top:36px;padding-top:24px;font-size:var(--small-size);color:var(--muted)}
.footer-languages,.footer-legal{display:flex;gap:10px 18px;flex-wrap:wrap}
.footer-languages{margin-top:24px}
.footer-languages a[aria-current]{color:var(--accent-dark);font-weight:var(--weight-semibold)}
@media(min-width:961px){.nav-drawer,.nav-veil{display:none!important}}
@media(max-width:1280px){
  :root{--display-size:58px}
  .topbar-row{gap:22px}
  .tabs a{padding-inline:11px;font-size:14px}
  .tabs a::after{left:11px;right:11px}
}
@media(max-width:1120px){.topbar-row{gap:14px}.tabs a{padding-inline:8px;font-size:13px}.bar-end{gap:8px}}
@media(max-width:960px){
  .desktop-nav{display:none}
  .bar-end{margin-left:auto}
  .nav-toggle{display:flex}
  .topbar-row{gap:12px}
  .footer-grid{grid-template-columns:1fr 1fr;gap:32px}
  .footer-brand{grid-column:1/-1}
  .grid-five{grid-template-columns:repeat(3,minmax(0,1fr))}
}
@media(max-width:768px){
  :root{--gutter:20px;--display-size:36px;--heading-size:28px;--space-section:48px}
  .grid-three{grid-template-columns:1fr}
  .grid-five{grid-template-columns:repeat(2,minmax(0,1fr))}
  .cta-row{margin-top:24px}
  .footer-grid{gap:24px}
}
@media(max-width:640px){
  .no-break{white-space:normal}
  .tilt,[data-tilt]{transform:none}
  .decor-region,.hero{max-width:100%;overflow-x:clip}
  .topbar-row{gap:8px}
  .brand{font-size:16px;gap:7px}
  .brand img{width:28px;height:28px}
  .bar-end{gap:6px;margin-left:auto}
  .lang{padding-inline:8px;font-size:12px;gap:4px}
  .lang svg{display:none}
  .nav-login{padding-inline:12px;font-size:13px}
  .nav-toggle{min-width:44px}
  .footer-grid{grid-template-columns:1fr}
  .footer-brand{grid-column:auto}
  .footer-bottom{align-items:flex-start;flex-direction:column}
}
@media(max-width:360px){
  :root{--gutter:16px}
  .brand{font-size:15px;gap:5px}
  .brand img{width:25px;height:25px}
  .bar-end{gap:4px}
  .lang{padding-inline:6px;font-size:11px}
  .nav-login{padding-inline:9px}
  .grid-five{grid-template-columns:1fr}
  .btn{padding-inline:20px}
}
@media(prefers-reduced-motion:reduce){
  html{scroll-behavior:auto}
  *,*::before,*::after{transition-duration:0s!important;animation-duration:0s!important}
  .reveal,.reveal.pending{opacity:1;transform:none}
}